Emerald
Minerals form a big part of the world’s economy. The contribution of minerals cannot be undermined; everything in the world depends on oil. Production, transport, farming, and many other industries depend on oil. Minerals are also ornamental, prestigious, and rare. One such kind of mineral is emerald. The word emerald is derived from a Semitic language through old French: esmeraude and Middle English Emeraude. Emerald’s worth, importance, and its rich history make it such an interesting mineral.
Physical and Chemical Properties.
Emerald is of the variety of the mineral beryl (Be3Al2(SiO3)6) of gemstones. Beryl is a beryllium aluminum silicate. Emeralds have a formula mass of 537.50, a refractive index of nω = 1.564–1.595,nε = 1.568–1.602 (Whaley et al. 15). It is green color due to traces of chromium and vanadium. Generally, the resistance to breakages of most emeralds is poor. On a Moh’s scale, the gemstone value is 7.5 to 8.0 (18). All colored gemstones are graded using four basic parameters color, clarity, cut, and carat weight. The color of gemstones is considered the most important criterion in grading gemstones. In gemology, color is often composed of three things: hue, saturation, and tone. The hues from emerald range from blue-green to yellow-green, green is the primary hue.
Gems that are medium to dark are the only ones considered emeralds, and on a scale where 0% is colorless, and 100% opaque black, emeralds are 75% in tone. Transparent emeralds are rare. Normally, emeralds have surface-breaking fissures and embodiments. Unlike Diamond, that requires magnification to grade emeralds use eye grading. Emeralds are oiled before grading to distinguish them as many stones have breaking fissure. A carat is equivalent to 200 milligrams.
The structure of emerald crystals is hexagonal. Other types of green beryl do not have a hexagon crystal structure and have colored by the presence of iron (Rapaport 45). A cubic centimeter of pure water has a weight of one gram and a specific gravity of 1.00. Sapphire- a type of emerald specific gravity is 4.00; thus, sapphire weighs for times more than water.
Emerald stability and clarity are improved by oiling as part of the post-lapidary course. This is done to refill cracks that reach the surface. Cedar oil is widely accepted and used in this process. For effective filling of cracks, the treatment is done under mild heat in a fume chamber. Disclosure is required by the United States Federal trade commission when an oil-treated emerald has been bought. Oil treatment is adopted in gem trade though similar un-treated gems are much worth. The use of green-tinted oils is illegal in the gem trade. A four-step scale is used to grade gemstones according to the level of their enhancement. Enhancement can be none, minor, medium, and high. A gem grade, none has visible inclusions. Emeralds can be imitated using man-made materials.
Uses
Emerald is used in culture and belief, where it is observed as the traditional birthstone for May and a time-honored gemstone for the astrological sign of Cancer (June 22 to July 22). One of the most fanciful tales about emeralds was narrated by the 16th-century soldier and historian Pierre de Bourdeille, seigneur. Pierre de Bourdeille, seigneur, cited several impressive emeralds a Spanish called Cortez carried to Europe from Latin America. One that caught his attention has a text Inter Natos Mulierum non sur-rexit mayor (“Among those born of women there has not risen anyone greater,” Matthew 11:11), which referred to John the Baptist in the Bible. Pierre de Bourdeille, seigneur considered the etching on such an adorable and simple mineral religious. He later dedicated work and the demise of King Charles IX of France, who died soon after that. One of India’s most known temple chief deity goddess Meenakshi idol is believed to have been made of emerald.
Emerald is among the four gemstones that are considered precious, including diamond, ruby, and sapphire. Emeralds are used to make the most expensive jewelry depending on the brand of the jewelry, the trending fashion, and the quality of treatment (Jauregui 17). Emeralds were used to make crowns for kings and emperors as they were viewed to be prestigious. Ancient tales narrate that, an emerald can help see the future by putting it under the tongue, emerald prevent the loss of memory and enhances creativity, and a love potion to tell the truth of vows. In modern times emerald is thought to relax eye strain.`
Location
Gemstones in the United States are found in Montana, Nevada, North Carolina, and South Carolina. America consumes 75% of the emeralds produced in the world. Emeralds were mined in Egypt at Mount Smaragdus since 1500 BCE, India, and Austria since the 14th century. The mines in Egypt were utilized on an industrial scale by the Roman Empire, and later the conquerors from Israel, the mines were later deserted upon the discovery of the mines in Colombia. Only ruins are found in these mines. Colombia remains the world’s largest producer of emeralds contributing to 50-95% of the world’s emerald production. Muzo, Coscuez, and Chivor are the three main Emerald producing mines in Colombia. A rare type of emerald called Trapiche is found in Colombia. Trapiche is unique due to its ray-like spokes of dark impurities.
Zambia is the second world’s largest producer of Emerald. The Kagem mines located along with the deposits of river Kafubu, Zambia is responsible for the production of 20% of quality gemstones (Ren et al.). Emeralds are found all over the world in countries such as Australia, Russia, Canada, Switzerland, Spain, Italy, and Brazil. Research has been done on whether an emerald that is already in the market origin can be found. Past research used qualitative aspects, which include; color, design, and quality of cut, method of crack filling, and anthropological details on the mineral to determine its source of origin (Groat et al. 26). Modern technology has helped studies use the energy-dispersive X-ray spectroscopy process, which has helped discover trace chemical element comparison between emeralds. This can even show emeralds that are from the same mines. David Cronin, an American gemologist, critically tested the chemical properties of emeralds using fluid dynamics and precipitation; his study depicted that emeralds from the same mines had the same chemical properties.
Synthetic emeralds are man-made emerald produced through chemical processes. Synthetic emeralds have a similar structure and chemical properties to that of natural emeralds. Flux-growth and hydrothermal synthetics are produced. In 1848, a French chemist Jacques Joseph Elbman started the flux process. One hundred years later, Carroll Chatham produced the first marketable emeralds (Holloway 21). The flux process involves growing synthetic crystals in flux liquid under high temperatures. Emeralds from the flux process resemble natural emeralds and require trained gemologists to distinguish. One distinguishing feature is that they have a slightly high value of gemological properties that include specific gravity, birefringence, and refractive index. In the hydrothermal process, crystals are formed in acidic water solutions at high pressure and temperature. This process is closely similar to the natural process, and it produces authentic emeralds. They are sold under the name symeralds and only sell at 5% to 10% compared to that of natural emeralds.
Value
Emeralds are the rarest gemstones. Commercially graded gemstones are many, but the fine quality is very rare. Like other gemstones, emeralds that are large in size are rare. Commercial class emeralds cost $ 30 to $ 525 (Karampelas et al 29), good quality cost $525 to $1125 (29), fine quality goes at $1125 to $ 2900 (29), and extra-fine costs $2900 to $9800 (30). High-quality emeralds can cost more than diamond one a carat measurement. Color is the most important aspect in valuing emeralds, but carat weight, cut, and clarity are also used. Traders consider vivid green and blue-green with uniform saturation and without zones as the best. The most valuable emeralds are transparent. They range from not being too light and not too opaque. In 2011, a necklace owned by Elizabeth Taylor was sold at a price of $6.5 million, which means a single carat priced at $280,000.
Emerald is an exciting mineral to study due to its many fanciful tales, a rich history, and the prestige it is held with in many parts of the world. Tales, including those from the Bible, make it even more amazing. Its rareness makes it have a high value compared to the other gems. However, there are imitations made of glass, and consumers should be cautious.
Works cited
Groat, Lee A., et al. “A REVIEW OF ANALYTICAL METHODS USED IN GEOGRAPHIC ORIGIN DETERMINATION OF GEMSTONES.” Gems & Gemology 55.4 (2019).
Holloway, Garry Ian. “Gemstone periphery light qualification system.” U.S. Patent Application No. 16/428,960.
Jauregui, Estefania Salgado. “Didactic Module of Colombian Emeralds and the Perspective of Geoparks: An Alternative for Conservation and Sustainable Management in Boyacá, Colombia.” The Journal of Purdue Undergraduate Research 6.1 (2016): 26.
Karampelas, Stefanos, et al. “Emeralds from the Most Important Occurrences: Chemical and Spectroscopic Data.” Minerals 9.9 (2019): 561.
Rapaport, Martin. “Methods for evaluating gemstone shape.” U.S. Patent No. 10,228,238. 12 Mar. 2019.
Ren, Junping, et al. “Zircon U–Pb and biotite 40Ar/39Ar geochronology from the Anzan emerald deposit in Zambia.” Ore Geology Reviews 91 (2017): 612-619.
Whaley, Cynthia H., et al. “GEM-MACH-PAH (rev2488): a new high-resolution chemical transport model for North American polycyclic aromatic hydrocarbons and benzene.” Geoscientific Model Development 11.7 (2018): 2609-2632.